# SDR AALA20110503SFO01

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 3, 2011
- Submitted: May 6, 2011
- Operation: Air carrier
- Aircraft: N183AN
- Make and model: Boeing 757223
- Aircraft serial: 29593
- Aircraft time: 45,357 hours, 11,918 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Fmc
- Part number: 4052506955
- Condition: Malfunctioned
- Location: Nr 1
- Stage of operation: CL
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA20110503SFO01

## Discrepancy

SFO - CREW REPORTED BOTH FLIGHT MANAGEMENT COMPUTERS DISPLAYED "STANDBY ONE" AND ALL NAV FUNCTIONS (INPUTS) WERE LOCKED OUT.  BOTH ROUTE 1 AND 2 UNUSABLE.  FLIGHT RETURNED SFO LANDED WITHOUT INCIDENT.  REPLACED THE NUMBER 1 FLIGHT MANAGEMENT COMPUTER.  SYSTEM GROUND CHECK NORMAL OPERATION.

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